1. Field of the Invention
The present invention generally relates to an endomedullary nail for the treatment of proximal femur fractures, such as for example pertrochanteric fractures whose fissure extends from the lesser to the greater trochanter, medial fractures and at the base of the femur neck, and the like.
The nail comprises an elongate body having a proximal portion and a distal portion. In the proximal portion thereof, the nail also comprises a first and a second hole, each having a transversal axis to the proximal portion axis for a corresponding cephalic screw.
The present invention also relates to a device for the treatment of proximal femur fractures comprising the above-mentioned nail and the corresponding cephalic screws.
2. Description of the Related Art
The now widespread use of endomedullary nails as above for the osteosynthesis of proximal femur fractures is known.
Fracture stabilisation is mainly obtained by means of two cephalic screws. The latter are inserted transversally to the nail into two respective circular holes of the proximal portion so as to cross the femur neck spongiosis up to reach the femur head in order to allow a mutual stump compression.
The cephalic screw arrangement and orientation with respect to the endomedullary nail substantially depend on the fracture type. In particular, according to the seriousness, the femur neck composing structure, the patient's age and the trauma type, fragments and fissures, which are different from each other, can be formed.
In most known nails, the two holes for cephalic screws have parallel axes.
On the contrary, for other types of trauma, mainly in case of serious pertrochanteric fractures, wherein it is necessary to ensure a certain nail and screw staticity, the two proximal holes have convergent axes. Therefore cephalic screws, once being inserted into the femur neck, mutually converge ensuring a high stabilisation thereof and the head. A nail with convergent-axis holes is known for example from the patent EP 0 853 923 in the name of the Applicant.
A further intramedullary femoral nail for the treatment of fractures is known from U.S. Pat. No. 5,549,610A in the name of RUSSEL et al. The nail includes three proximal locking screw passageways, two parallel upwardly oblique passageways and a single downwardly oblique passageway. The two parallel upwardly oblique passageways are suitable for the insertion of two cephalic screws in the head of the femur in reconstruction mode and the single downwardly oblique passageway is suitable for insertion of one screw transversally in the neck of the femur in a femoral mode.
Another nail is known from the Japanese patent application JP 2002253566 in the name of MIZUHO. This nail comprises in its own proximal portion opposite slots wherein from 2 to 6 screws can be inserted. The screws are inserted in mutual crossing in the opposite slots in mutual engagement. A tip is provided which is inserted in the head portion of the nail and it presses the screws against each other.
However, known nails, although ensuring a complete fracture stabilisation, have recognised drawbacks being not yet overcome.
The main drawback is that, just to ensure the containment of a particular type of fracture, the nail and cephalic screw configuration is substantially predetermined, restraining and limiting the possibility to change the endomedullary nail application in different traumatic situations.
It results that the use of known endomedullary nails for the stabilisation of fractures having a different nature is considerably limited, since this would inevitably involve a wrong arrangement and orientation of the two cephalic screws.
This drawback is even more serious when considering that, according to the type of femur fracture, a surgeon is obliged to exclusively choose preliminarily, i.e. before the intervention, the endomedullary nail to be used and he cannot change the orientation of the two cephalic screws when the nails has already been implanted.
The aim of the present invention is that of providing an endomedullary nail overcoming the above-mentioned drawbacks in order to have a higher application versatility and, particularly, allowing a surgeon to change the cephalic screw configuration when operating during the surgical intervention.
A further aim of the invention is that of providing an endomedullary nail allowing a surgeon to change the cephalic screw configuration without requiring the nail removal from the medullar cavity.
Another aim of the present invention is that of providing a nail allowing to obtain at least two different screws fixing configurations.